For a streamlined ecommerce process why not have your website automatically update customer records and create sales invoice on the fly for you?
Yes it's possible... you can sit back and all the work is done for you. Depending on the capabilities of the particular accounts package the possibilities are endless. The project we are tackling will also deal with account customers paying at a later stage. All you would need to do is update the payment status in the website and the invoice status is automatically updated in the accounts package also.
APIs (Application Programming Interfaces) allow websites to securely transmit data triggering defined tasks. Payment gateway services like Paypal, Braintree etc have been using these methods for a while and now accounting packages can do the same. In reverse these services usually have something called Webhooks which basically fire data back to your website when you change things on their end. As long as the correct listener code has been set up then this can be used to update your system on the fly.
If you're interested in any API integration on your web services, get in touch.